1. Field of the Invention
The present invention relates to a multi-lens vision correction method and its apparatus that adopt a non-surgical method to correct focusing images on a Retina of a person to solve a myopia problem caused by the person's habits. In addition to providing a tool for recovering a person's normal vision, the invention also keeps the Ciliary Body and Lens of the person's eyes operated in a range of sight with a relatively far distance to change an old bad habit of getting used to a narrower visual environment and prevent the myopia problem caused by the bad habit from being deteriorated. If a person has a pseudomyopia problem, then the normal naked eye's vision can be recovered gradually by using the method of the invention. A lens module having two lenses is used as a basic structure, and a concave lens is used at a position closer to an eye and preferably having the smallest feasible distance from the eye to correct the focusing of an eyesight and let people see an object at a far distance. The lens, closer to the eye, of the invention also corrects the eyesight with excessive minus optical power compensation, and the lens at a distance farther from the eye is a convex lens having opposite optical power characteristics with the lens at a distance closer to the eye according to the excessive compensation, and the invention uses and selects a lens combination with appropriate optical power, so that the final image can be produced at a position closer to the front along the central optic axis, and the virtual image of an object converted by the lens module can be designed, controlled and converted at a farther distance to change the old habit of a person. The visual environment of a myopic person is extended from a short distance to a longer distance, and the myopic person's eyes can sense a farther and bigger object, and the Ciliary Body and Lens can move properly to the focus and form a final image at the Retina, unlike the general movement made by naked eyes to observe an object. The myopic person will use their eyesight to view objects at a zone farther than the actual distance. With the application of the present invention, the perceived space will be apparently larger than the real space. An eye will therefore accommodate differently by Ciliary Muscles in such a perceived environment with clear eyesight. By a natural correction with the physiology of sight and balance of users' habit by changing one's visual environment, pseudomyopia can be balanced and abnormal elongation of the axial length of an eye due to bad habits can be stopped, and thus achieving a vision correction effect.
2. Description of the Related Art
According to the principle of the physiology of sight, extrinsic muscles control an eyeball to be aligned with the optic axis of an object, and after a visible light is bombarded at and reflected from the object, the light passes through a Cornea, an Anterior Chamber and an Aqueous Humor in a Posterior Chamber, a Lens, and a Vitreous Body contained in a Sclera to form an inverted real image on a Retina. If the image produced on the Retina cannot be focused, then involuntary muscles in a Ciliary Body receive an instruction given by Oculomotor Nerves to move and change the shape of the Lens to change its optical power until the image can be focused clearly, and then the Retina senses an image signal, and the Optic Nerves send the image signal for the interpretation of the image by a cerebrum for further information processing.
There are many reasons that myopia cannot be improved, and one of the reasons is a person's bad habit of using eyes because of staying in a narrower visual environment and getting used to the narrow visual environment. Since an abnormal use of eyes causes the muscle in the Ciliary Body to be used continuously in a particular direction, so that the muscle itself and the eye Lens may be used excessively and cannot restore themselves naturally. Pseudomyopia is caused by a convulsion or a cramp of the Ciliary Muscles that controls the near vision, and thus an excessively accommodated Lens cannot release the convulsion. If a person keeps doing the same as described above for a long time, the axial length of the eyeballs will be elongated, particularly at the stage of a physiological development of the eyeballs and vision. If a person does not pay attention to such bad habit, the final image can no longer be focused on the Retina anymore, and a severe myopia will result that will further cause terrible pathological changes such as a peel-off of the Retina to myopia patents. At present, we understand that the problem of light and medium levels of myopia is not very serious, and myopic persons can see things clearly with a vision correction, but there may be a serious problem to a critical level of myopia and those people have to bear a terribly high risk of the eye health. With further understanding to the problem, the causes of myopia must be controlled and improved, or else a terrible consequence will result. Besides pathological changes and other causes, a person's abnormal habit of using eyes is an important factor that demands much more attentions. Some of these habitual behaviors will be passed on to the next generation, and the next generation will have similar bad habits causing myopia more easily.
Traditional vision correction methods for myopia aim at the problem of focusing an image in front of a Retina and use a single diverging lens (which is a concave lens in the air) to correct the abnormal focusing. These vision correction methods surely can recover the normal vision of a myopic person, but it cannot change the person's habit by changing one's visual environment, and thus the person keeps the old habit of using eyes, and thus most of the myopic persons maintain their myopia or even gain an increase of the level of myopia. A multi-focal lens for a vision correction can retard the habit, but a lens of the same nature cannot balance a myopia person's old habit. It is because the traditional single lens correction methods compress one's visual environment. We can see the proof in latter description of this specification. Therefore, a traditional single multi-focal lens used for progressively reducing the absolute value of the optical power only reduces the level of compression, and it still compresses the visual distance. In the real world, it is very rare for myopic persons to recover their normal vision, since the traditional vision correction methods cannot remove their bad habits. There are many vision training machines or methods available in the market, but the difficulties of these machines and methods reside on that human vision is an important tool for obtaining information, and once the vision of a person is blurred, trainings in a limited short time can provide a very little effect on the vision correction, and it is thus a major cause for the critical-level myopia, and such problem cannot be improved completely in an easy manner. We need some special methods to effectively train involuntary muscles in a Ciliary Body. We definitely need to have a good vision correction method for people who have vision problems to see things clearly as well as an apparatus for changing a person's bad habit, and thus improvements and feasible solutions to this problem are needed.